Welcome to R2R!! Like stated before. Use a tub big enough for your livestock, heater, and circulation pump. The key is maintaining parameters throughout all this. This is where I went wrong when I transferred my tanks. My livestock was in a tub for a week. I moved everything over to my new tank with all new tank water. ALK was a 4 dkh difference and I lost a couple acros because of it.
Welcome! When I transferred my 75 gal fish to my 180 gal, I added the water from the 75 gal to the new tank and matched ph, temp, and salinity. No losses.